Pituitary Pars Intermedia Dysfunction (Equine Cushing’s Disease) in Nondomestic Equids at Marwell Wildlife: A Case Series. One Chapman’s Zebra (Equus Quagga chapmani) and Five Przewalski’s Horses (Equus Ferus przewalskii).

This research article talks about the presence and treatment of a condition known as Pituitary pars intermedia dysfunction (PPID), or equine Cushing’s disease, in nondomestic equids, especially one Chapman’s zebra and five Przewalski’s horses. The condition, previously observed primarily in middle-aged to older domestic horses, was diagnosed using basal adrenocorticotropic hormone (ACTH) tests, and its symptoms were managed with pergolide mesylate.

Identification of PPID in nondomestic equids

• The study focuses on the identification and diagnosis of Pituitary pars intermedia dysfunction (PPID) in nondomestic equids, primarily one Chapman’s zebra and five Przewalski’s horses. It previously has been extensively reported in middle-aged to older domestic horses, but only in one nondomestic species, the onager.
• The researchers diagnosed this condition through the observation of consistent clinical, hematological, and pathological findings. These findings include similar gross and histopathological examinations of the pituitary gland that revealed either pars intermedia adenomas or adenomatous hyperplasia. These pathological conditions are similar to findings in domestic equids affected by PPID.

Use of basal ACTH testing

• A significant part of this study involved the use of basal adrenocorticotropic hormone (ACTH) tests for the diagnosis and monitoring of PPID in these zoo animals. This hormone assessment method is clearly important in helping with the identification of the disease.
• Successive tests would offer a means of monitoring the progression of the condition over time and the effectiveness of any introduced therapeutic interventions.

Treatment with pergolide mesylate

• Concurrently, the researchers also utilized a therapeutic intervention known as pergolide mesylate. This medication has been used to reduce the basal ACTH concentration, and consequently, reduce the clinical indications associated with PPID in the studied animals.
• The reduction of these symptoms is crucial in managing the overall health of these nondomestic equids and in improving their welfare.

Implications of the findings

• The study concludes with the suggestion that clinicians working with nondomestic equids should be aware of PPID and consider implementing regular screening, especially since improvements in management and veterinary care for exotic animals have resulted in older captive populations.
• Early diagnosis and treatment of PPID can prevent the development of painful clinical sequelae, potentially improving the welfare of zoo equids.